1. Field of the Invention
The present invention relates to a configuration of a plasma display panel, and more particularly to a configuration of a plasma display panel which can decrease the address discharge voltage and can prevent the dispersion of voltage.
2. Description of the Related Art
A surface discharge type AC plasma display (hereafter PDP) normally forms a discharge space by sealing discharge gas between two glass substrates facing each other. One glass substrate side (hereafter front substrate) of the two glass substrates, and a plurality of row electrode pairs which extend in the row direction, are formed in parallel in the column direction, and the plurality of row electrode pairs are covered by a dielectric layer.
On the other glass substrate side (hereafter rear substrate) of the two glass substrates, a plurality of column electrodes, which extend in the column direction, are formed in parallel in the row direction. And in an area facing the portions of the discharge space where the row electrode pairs and the column electrodes are crossed, discharge cells having red, green and blue fluorescent layers are formed, and these discharge cells are arrayed in a matrix on the panel face.
For the discharge gas sealed between the two glass substrates, discharge gas containing xenon of which volume ratio 1 to 10%, for example, is used.
In a PDP having this structure, an address discharge is selectively generated between one row electrode, out of the pair of row electrodes forming the row electrode pair, and a column electrode and an emission cell (discharge cell where a wall electric charge is formed in a dielectric layer of the counter portion) or a non-emission cell (discharge cells where a wall electric charge is erased in the dielectric layer of the counter portion) is selected. By this, the emission cells and non-emission cells are distributed on the panel face corresponding to the image data of the video signal.
When a sustain pulse is alternately applied to the row electrodes forming a pair of each row electrode pair, a sustain discharge is generated in an emission cell, and by this sustain discharge, a vacuum ultraviolet ray is generated from the xenon in the discharge gas in the discharge space. By the generated vacuum ultraviolet ray, red, green and blue fluorescent layers in each emission cell are excited and visible lights are generated, and as a result, an image corresponding to the image data based on the matrix display is formed on the panel face.
In a PDP having the above configuration, conventionally the dimensions of the row electrode have been set as follows.
FIG. 1 shows a plane configuration of a portion having one discharge cell C, out of a row electrode pair of a conventional PDP, and in FIG. 1, the row electrodes X and Y, which constitute a row electrode pair (X, Y), comprise strip type transparent electrodes Xa and Ya which extend in the row direction in parallel with each other, and face each other via a discharge gap g in a column direction, and strip type bus electrodes Xb and Yb, which are electrically connected to the transparent electrodes Xa and Ya and extend in a row direction respectively.
In FIG. 1, D is a column electrode.
The width W of each row electrode X and Y of this conventional PDP is generally set to a value of 400 to 1000 μm (e.g. see Japanese Patent Application Laid-Open No. H8-22772).
And in this conventional PDP, the width of the row electrode in the column direction is set as above for the following reason.
In other words, in PDP, the fluorescent layer is excited by a resonance line, which is a main component of the vacuum ultraviolet ray generated from xenon in the discharge gas by a sustain discharge and has a wavelength of 147 nm, and visible light is generated, and in the process of propagating through the discharge gas toward the fluorescent layer, the resonance line collides with xenon atoms in the discharge gas, and attenuates due to absorption and radiation which repeats with xenon atoms.
Therefore in the case of PDP in which discharge gas, of which partial pressure of xenon is low, such as a volume ratio of xenon containing 1 to 10%, is sealed in, the quantity of the resonance line which reaches the fluorescent layer during sustain discharge decreases, and the required brightness may not be acquired.
Therefore in a conventional PDP, the width w of each row electrode X and Y in the column direction is set wide, as shown in FIG. 1, so that a sustain discharge is generated in a wide area in the discharge cell C, and the quantity of vacuum ultraviolet rays (that is the quantity of the resonance line) generated by the sustain discharge is increased so that the quantity of the resonance line which reaches the fluorescent layer becomes more than a predetermined value, and brightness more than a predetermined value is secured.
However in the configuration of the conventional PDP, the high emission efficiency required for creating a high brightness screen cannot be implemented.
To solve this problem, the present inventors discovered a preferable mode after considering various ideas and experiments, and proposed this in the previous application (Japanese Patent Application No. 2005-241274).
A characteristic of the mode disclosed in this previous application (hereafter simply called “previous application”) is that the respective width in the column direction of a pair of row electrodes, constituting the row electrode pair, at a portion related to the discharge which is performed via the respective discharge gap, is set to 150 μm or less, and discharge gas of which partial pressure of xenon is set to 6.67 kPa or more is sealed in the discharge space between the front glass substrate and the rear glass substrate.
However further examination by the present inventors showed that this characteristic structure of the previous application secures brightness more than a predetermined value, but the address discharge voltage is increased, and the address discharge voltage disperses due to an accuracy error in the panel structure.